Safety concept for batteries

Abstract

A safety device for a battery having battery cells that are configured to connect to poles of the battery via charging and isolating devices includes a discharge device. The discharge device is configured to connect in parallel to the battery cells. The discharge circuit can include at least one discharge resistor and an electronic valve. The electronic valve is configured to switch on and off. The discharge circuit can be configured to activate with a battery management system.

The invention claimed is: 
     
       1. A safety device for a battery, comprising:
 a discharge circuit configured to connect parallel to battery cells when a disconnection of battery cells from at least one pole of two poles of the battery is detected, 
 wherein the battery includes the battery cells configured to connect to poles of the battery via charging and isolating devices. 
 
     
     
       2. The safety device as claimed in  claim 1 , wherein the battery is a traction battery. 
     
     
       3. The safety device as claimed in  claim 1 , wherein the discharge circuit includes at least one discharge resistor and an electronic valve, wherein the electronic valve is configured to switch on and off. 
     
     
       4. The safety device as claimed in  claim 3 , wherein the electronic valve comprises a semiconductor switch or an electromechanical switch. 
     
     
       5. The safety device as claimed in  claim 1 , wherein the discharge circuit is configured to activate with a battery management system. 
     
     
       6. The safety device as claimed in  claim 1 , further comprising:
 an inverter configured to connect to the poles of the battery, the inverter is connected to a battery management system and is configured to actuate using the battery management system to discharge the battery. 
 
     
     
       7. The safety device as claimed in  claim 1 , further comprising:
 electronics configured to equalize state of charge of the battery cells, 
 wherein the electronics include balancing resistors and are connected to a battery management system, the electronics are configured to actuate using the battery management system and the balancing resistors are configured to discharge the battery cells. 
 
     
     
       8. A method for discharging a battery, comprising:
 detecting a disconnection of battery cells from at least one pole of two poles of the battery using a battery management system; and 
 connecting a discharge circuit of a safety device parallel to the battery cells using a battery management system if the disconnection is detected, 
 wherein the battery includes the battery cells configured to connect to the two poles of the battery via charging and isolating devices. 
 
     
     
       9. The method as claimed in  claim 8 , further comprising:
 sending actuation signals, using the battery management system, to the discharge circuit to connect the discharge circuit parallel to the battery cells. 
 
     
     
       10. The method as claimed in  claim 8 , further comprising:
 discharging the battery cells after the disconnection of the battery cells from the two battery poles.